Highlights
• Heavy rainfall is predicted for Eastern
province from 1st Jan – 4th Jan. Greater likelihood of wet
tendency is predicted for Sri Lanka from Jan - Mar.
• Dry conditions with below average
rainfall was observed in the entire island last week except for fairly heavy
rainfall in the Southern
province with max of 94.5 mm in Matara district on 22nd
Dec.
• From 21st Dec - 28th Dec, up to 45 km/h Northeasterlies were
experienced across the island.
• Sea surface temperatures were
neutral around the entire island.
Predictions
Rainfall
14-day prediction:NOAA NCEP models:
From 1st – 4th January:
Total rainfall by Provinces
- 105 mm - Eastern
- 95 mm - Uva
- 75 mm - Northern, North Central
- 65 mm - Southern
- 55 mm - Central
- 45 mm - Sabaragamuwa
- 35 mm - North Western, Western
From 5th – 11th January:
Total rainfall by Provinces:
- 75 mm - Eastern
- 65 mm - Uva
- 55 mm - Southern
- 45 mm - Sabaragamuwa
- 35 mm - Central, North Central, Western
- 25 mm - Northern, North Western
MJO based OLR predictions:
For the next 15 days:
MJO
shall be active during 1st – 12th January giving
significantly suppressed rainfall from 1st – 2nd January
and sightly suppressed rainfall from 3rd – 12th
January for the entire island.
Ocean State (Text Courtesy IRI)
Pacific Sea Sate: December 22, 2021
Equatorial sea
surface temperatures (SSTs) are below average across the central and
east-central Pacific Ocean in the mid-December. The tropical Pacific atmosphere
is consistent with La Niña conditions. A large majority of the model forecasts
indicates very high probabilities of La Niña during the Northern Hemisphere
winter, weakening gradually, and likely to dissipate in Mar-May 2022.
Indian Sea Sate
Sea
surface temperatures were neutral around the entire island.
Interpretation
Monitoring
Rainfall:
During the last two weeks, there had been fairly heavy rainfall over the following
provinces: Southern.
Wind:
Northeasterly winds prevailed in
the sea area and around the island last week.
Temperature:
The temperature anomalies were 10C - 30C above
neutral for some parts of Central, Sabaragamuwa and Western provinces last
week, driven by the warm SST’s.
Predictions
Rainfall:
During the next week
(1st– 4th January) heavy rainfall is predicted for Eastern
province.
Temperature:
The temperature remains normal during 1st January – 8th January for the entire island.
Teleconnections:
La Niña - The SST forecast indicates that La Niña is favored to continue through the
Northern Hemisphere winter.
MJO
shall be active during 1st – 12th January giving
significantly suppressed rainfall from 1st – 2nd
January and sightly suppressed rainfall from 3rd – 12th
January for the entire island.
Seasonal Precipitation:
The precipitation forecast for the Jan-Mar season show enhanced
probabilities of above-normal precipitation over Sri Lanka.